CVE-2026-53328: Linux kernel · sched_ext: Don't warn on NULL cgrp_moving_from in scx_cgroup_move_task()
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 7.0.0-31.31~24.04.1 : update Linux kernel when convenient.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 5% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 7.0.0-31.31~24.04.1, 7.0.0-31.31, 7.0.0-1012.12 +7
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 1 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and fixed versions include 7.0.0-31.31 and later variants. Users should upgrade to these fixed kernel versions to resolve the issue. No additional mitigation is required as the warning was unnecessary and the fix removes it.
Description
A vulnerability in the Linux kernel's sched_ext subsystem caused a warning to trigger incorrectly when systemd's user manager wrote certain controls to its own subtree_control while a sched_ext scheduler was loaded. This warning was due to a NULL pointer condition in the cgroup migration logic, which was a legitimate scenario but improperly handled. The issue has been fixed by removing the unnecessary warning. The vulnerability affects specific Linux kernel versions and has been addressed in later fixed releases.
References
- ubuntu.com/security/CVE-2026-53328 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-53328 (opens in a new tab)
- git.kernel.org/linus/02e545c4297a26dbbc41df81b831e7f605bcd306 (opens in a new tab)
- git.kernel.org/stable/c/02e545c4297a26dbbc41df81b831e7f605bcd306 (opens in a new tab)
- git.kernel.org/stable/c/0ffcad63b19a1cadb475c9f405a93607fdcd0d7c (opens in a new tab)
- git.kernel.org/stable/c/bc75f5951fac4e49d175c4433fc08fb1ec01172f (opens in a new tab)
- git.kernel.org/stable/c/cdff2eb97be147d2ce52ac1327841068781f25dc (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)